<template>
  <div class="todo-footer" v-show="this.total">
    <label>
      <!-- <input type="checkbox" :checked="isAll" @change="checkAll"> -->
      <input type="checkbox" v-model="isAll" />
    </label>
    <span>
      <span>已完成{{ doneTotal }}</span> / 全部{{ total }}
    </span>
    <button class="btn btn-danger" @click="clearAll">清除已完成任务</button>
  </div>
</template>

<script>
export default {
  name: "TodoFooter",
  data() {
    return {};
  },
  props: ["todos", "toggleDoneAll", "clearAllDone"],
  computed: {
    total() {
      return this.todos.length;
    },
    doneTotal() {
      // return this.todos.filter(item => item.done === true).length
      // 条件统计 reduce
      return this.todos.reduce(
        (pervious, current) => pervious + (current.done ? 1 : 0),
        0
      );
    },
    isAll: {
      get() {
        return this.doneTotal === this.total && this.total > 0;
      },
      set(value) {
        this.toggleDoneAll(value);
      },
    },
    /* isAll() {
      return this.doneTotal === this.total && this.total > 0;
    }, */
  },
  methods: {
    /* checkAll(e) {
        this.toggleDoneAll(e.target.checked);
    }, */
    clearAll() {
      confirm("确认删除吗？") && this.clearAllDone();
    },
  },
};
</script>

<style scoped>
.todo-footer {
  height: 40px;
  line-height: 40px;
  padding-left: 6px;
  margin-top: 5px;
}

.todo-footer label {
  display: inline-block;
  margin-right: 20px;
  cursor: pointer;
}

.todo-footer label input {
  position: relative;
  top: -1px;
  vertical-align: middle;
  margin-right: 5px;
}

.todo-footer button {
  float: right;
  margin-top: 5px;
}
</style>
